package com.winqai.security.app.authenticaiton;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.winqai.security.core.properties.SecurityProperties;
import org.apache.commons.codec.binary.StringUtils;
import org.apache.commons.collections.MapUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.core.Authentication;
import org.springframework.security.crypto.codec.Base64;
import org.springframework.security.oauth2.common.OAuth2AccessToken;
import org.springframework.security.oauth2.common.exceptions.UnapprovedClientAuthenticationException;
import org.springframework.security.oauth2.provider.*;
import org.springframework.security.oauth2.provider.token.AuthorizationServerTokenServices;
import org.springframework.security.web.authentication.SavedRequestAwareAuthenticationSuccessHandler;
import org.springframework.stereotype.Component;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 处理表单，短信，社交登入成功获取认证授权token
 */
@Component
public class WinqaiAuthenticationSuccessHandler extends SavedRequestAwareAuthenticationSuccessHandler {

    private Logger logger = LoggerFactory.getLogger(getClass());

    @Autowired
    private ObjectMapper objectMapper;

    @Autowired
    private SecurityProperties securityProperties;

    @Autowired//已配置
    private ClientDetailsService clientDetailsService;

    @Autowired
    private AuthorizationServerTokenServices authorizationServerTokenServices;

    @Override
    public void onAuthenticationSuccess(HttpServletRequest request, HttpServletResponse response, Authentication authentication) throws IOException, ServletException {
        logger.info("登入成功");

        //从BasicAuthenticationFilter拷贝解码流程
        String header = request.getHeader("Authorization");

        if (header == null || !header.startsWith("Basic")) {
            throw new UnapprovedClientAuthenticationException("请求头无client信心");
        }

        String[] tokens = extractAndDecodeHeader(header, request);
        assert tokens.length == 2;

        //=======构建OAuth2Request

        String clientId = tokens[0];
        String clientSecret = tokens[1];

        ClientDetails clientDetails = clientDetailsService.loadClientByClientId(clientId);
        if(clientDetails == null){
            throw new UnapprovedClientAuthenticationException("clientId对应的配置信息不存在："+clientId);
        }else if(!StringUtils.equals(clientDetails.getClientSecret(),clientSecret)){
            throw new UnapprovedClientAuthenticationException("clientSecret不匹配："+clientSecret);
        }
        //授权类型自定义custom
        TokenRequest tokenRequest = new TokenRequest(MapUtils.EMPTY_MAP,clientId,clientDetails.getScope(),"custom");

        OAuth2Request oAuth2Request = tokenRequest.createOAuth2Request(clientDetails);

        //
        OAuth2Authentication oAuth2Authentication = new OAuth2Authentication(oAuth2Request,authentication);

        OAuth2AccessToken token = authorizationServerTokenServices.createAccessToken(oAuth2Authentication);

        response.setContentType("application/json;charset = UTF-8");
        response.getWriter().write(objectMapper.writeValueAsString(token));
    }
    //从BasicAuthenticationFilter拷贝解码流程
    private String[] extractAndDecodeHeader(String header, HttpServletRequest request)
            throws IOException {

        byte[] base64Token = header.substring(6).getBytes("UTF-8");
        byte[] decoded;
        try {
            decoded = Base64.decode(base64Token);
        }
        catch (IllegalArgumentException e) {
            throw new BadCredentialsException(
                    "Failed to decode basic authentication token");
        }

        String token = new String(decoded, "UTF-8");

        int delim = token.indexOf(":");

        if (delim == -1) {
            throw new BadCredentialsException("Invalid basic authentication token");
        }
        //clientid 和 clientsecret
        return new String[] { token.substring(0, delim), token.substring(delim + 1) };
    }

}